6v or 12v ?????

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philz
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Controversial I know as we have fans of both on here. I wanted to remain 6v but starting is intermittent. One day first kick then next day nothing. Gone through all the wiring and connect direct from stator to coil (changed coil) makes no difference. I know the bike floods easy and I run on with fuel off for a short while and start without fuel on.
Im considering going 12v now, does it produce a stronger spark and are they as reliable as everyone says?
bristolmod
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a well maintained 6v points system will work well and produce a good spark- the only downside is that the lights aren't as good as 12v, although with a remagnetised flywheel they are pretty good. I ran a high reving Muggy on points a few years back and it never let me down- no misfires and no "points bounce" either!

The good thing about 6v points is that you can generally sort them out at the roadside and a clean/ adjustment will generally get you home.

12v produces good lights and spark, but if the system "fails" it fails and no amount of fiddling will get it going again- you have to replace components to get it sorted.

I'm a great believer in the old points system- the 12v stuff when it first came in was pretty reliable- not so sure now with the amount of comments on various scooter forums.

Chris
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scooterslag
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bristolmod wrote:a well maintained 6v points system will work well and produce a good spark- the only downside is that the lights aren't as good as 12v, although with a remagnetised flywheel they are pretty good. I ran a high reving Muggy on points a few years back and it never let me down- no misfires and no "points bounce" either!

The good thing about 6v points is that you can generally sort them out at the roadside and a clean/ adjustment will generally get you home.

12v produces good lights and spark, but if the system "fails" it fails and no amount of fiddling will get it going again- you have to replace components to get it sorted.

I'm a great believer in the old points system- the 12v stuff when it first came in was pretty reliable- not so sure now with the amount of comments on various scooter forums.

Chris
Yeah I second what Chris said , too many people have been happy to chuck away a pretty decent points set-up for a unreliable electronic kit, sounds like your problem is carb related, you running a Jettex carb?
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philz
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Dellorto Sh1/18 all stripped and ultrasonic clean new needle and good float. Fuel still creeps through though unless you shut off the tap. Not changed the slide but I didn't think that could cause the problem. Choke is spot on. I'm changing the loom at the moment as it is old and one thought was there maybe a wiring issue. Frustrated!!!!
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scooterslag
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could be a combo of problems chap, but yeah- worth binning the original loom if its a tad crappy, good luck with the fault find. Paul
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coaster
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6v and points systems has it's fans and I don't doubt they can be reliable but that will require frequent maintenance. I agree that problems are usually fixable roadside (providing you have a reasonable level of mechanical aptitude but it will still require removal of the rear runner, fan cowl and dust cap and probably the flywheel as well. If you are having to go that far, it's hardly any different from running an electronic and carrying some cheap 'get you home' spares. I carry a spare stator and a £4.99 eBay CDI just in case.
philz
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Well I decided to try the electronic 12v conversion and keep hearing about reliability but not in my case. I got a good fat spark from the green stator wire to frame, connect to CDI and nothing from the CDI to plug. Changed the CDI for another new one and still nothing, grrrrrrr. Am I missing something or could it be something else?. I'm assuming if the stator/ignition is producing a spark then I should be getting something from the CDI.
Daggs
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It's possibly misalignment of the pick-up in relation to the crossover magnets. Or a dud pick-up. Leave the green to ignition wire disconnected, to eliminate a switch/wiring issue.
philz
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Thanks Daggs am I correct in thinking that the pickup sends the signal to the CDI to send the spark to the plug, unlike points which constantly send the spark? If the pickup sends no signal no spark out of the CDI I'm beginning to think it's the pickup if that's the case. I will meter the pick up for resistance.
Daggs
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Yup, that's it.
Just think of the green wire (and therefore LT coil) pumping sparks into the CDi. But they'll go nowhere until the pick-up is triggered, causing a discharge along the HT.
I've had the problem when the pick-up was not close enough and also when the alignment up/down wasn't good enough.
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